Stabilized and Controlled Release of Radicals within Copper Formate-Based Nanozymes for Biosensing

Abstract

Fenton-like radical processes are widely utilized to explain catalytic mechanisms of peroxidase-like nanozymes, which exhibit remarkable catalytic activity, cost-effectiveness, and stability. However, there is still a need for a comprehensive understanding of the formation, stabilization, and transformation of such radicals. Herein, a copper formate-based nanozyme (Cuf-TMB) was fabricated via a pre-catalytic strategy under ambient conditions. The as-prepared nanozyme shows comparable catalytic activity (K m , 1.02 × 10 −5 mM −1 ; K cat , 3.09 × 10 −2 s −1 ) and kinetics to those of natural peroxidase toward H 2 O 2 decomposition. This is attributed to the feasible oxidation by *OH species via the *O intermediate, as indicated by density functional theory calculations. The key •OH radicals were detected to be stable for over 52 days and can be released in a controlled manner during the catalytic process via in situ electron spin-resonance spectroscopy measurements. Based on the understanding, an ultrasensitive biosensing platform was constructed for the sensitive monitoring of biochemical indicators in clinic settings.

Biocompatible copper formate-based nanoparticles with strong antibacterial properties for wound healing

“…The preparation of the Cuf-TMB nanoparticles was followed to our previous work [ 42 ]. For the synthesis of Cuf-TMB@PDA, dopamine (DA) solution (0.1 µg mL − 1 ) was mixed with Cuf-TMB suspension (78 µg mL − 1 ) in equal volumes under stirring at 380 rpm for 80 min at room temperature.…”